Multi-stage centrifugal pump



E. F. OGLES MULTI-STAGE CENTRIFUGAL PUMP 7 Feb. 13, 1968 Filed Ndv. 14, 1966 2 Sheets-Sheet 1 Q a w I I ii .u

INVENTOK ETHRIDGE E OGLES ATTORNEY Feb. 13, 1968 E. F. OGLE S 3,368,494

MULTI-STAGE CENTRIFUC'AL PUMP Filed Nov. 14, 1966 2 Sheets-Sheet 2 INVENTOR ETHRIDGE F OGLES BY M ww ATTORNEY United States Patent 3 Claims. (Cl. 103-108) This application is a continuation-in-part of US. Ser. No. 419,247, filed Dec. 17, 1964, and entitled Multi- Stage Centrifugal Pump, now abandoned.

This invention relates to a centrifugal pump, and more particularly to a multi-stage centrifugal pump, wherein a plurality of pump uni-ts may be interconnected to amplify the pumping force thereof, and has as its primary object the provision of a simplified and improved pump structure facilitating such assembly in multiple units.

This application constitutes an improvement on the previous application of Ethridge F. Ogles entitled Centrifugal Pump With Adjustable Impeller, Ser. No. 322,217, filed Nov. 7, 1963, now matured in the Patent No. 3,280,748 and incorporates certain of the principles of the previously filed application therein. A

A further important object of the instant invention resides in the provision of a pump of this character provided with connecting means whereby any desired multiplicity of units may be interconnected.

An additional object of the invention resides in the provision of a pump of this nature wherein the bearing seal is located adjacent the inlet of the pump, reducing the effective pressure thereon, and hence enabling a higher output.

A further object of the invention resides in the provision of a multiple-stage pump, consisting of a plurality of units connected in series, wherein each unit amplifies the eiiect of the other, resulting in a high performance pump assembly requiring minimum space.

Other objects reside in the combinations of elements, arrangements of parts, and features of construction, all as will be more fully pointed out hereinafter, and disclosed in the accompanying drawing wherein there is shown a preferred embodiment of the instant inventive concept.

In the drawings:

FIGURE 1 is a side view of a multistage pump assembly constructed in accordance with the instant invention.

FIGURE 2 is an exploded perspective view of the shaft seal construction.

FIGURE 3 is an enlarged fragmentary sectional view taken through the inlet end and one stage of the pump assembly.

FIGURE 4 is an exploded perspective view of the bearing assembly for the drive shaft of the pump assembly, and

FIGURE 5 is a side elevational view showing the external form of the impeller and manifold of a single stage of the pump, parts thereof being broken away.

Similar reference characters refer to similar parts throughout the several views of the drawings.

Having reference now to the drawings in detail, and more particularly to FIGURE 1, there is generally indicated at an electric motor or other source of power including a drive shaft 11 which is connected by any desired conventional coupling 12 to the drive shaft 13 of a multi-stage pump assembly, generally indicated at 14, and comprising a plurality of individual pump units 1'5, all of which are substantially identical, connected in series. The shaft '13, extends through a bearing assembly, generally indicated at 16, which, as best shown in FIG- URES 3 and 4, is comprised of an externally threaded bearing housing 17, which is threadedly engaged in an "ice opening 18 in annulus 19 carried by one end of a tapered supporting frame which includes tapered struts 20, which at their outer end are suitably secured to the flange 21 of the first pump housing 15. A bearing housing O-ring 22 seats within the bearing housing, and a bearing housing lock nut 23 secures .the housingfirmly in related assembly with the annulus 19. The housing 17 contains a pair of drive shaft bearings 24, consisting of inner and outer annuli 25 and 26 having ball bearings 27 positioned therebetween in conventional manner. A drive shaft lock washer 28 is provided, and secured in position by a drive shaft lock nut 29 which is mounted on the shaft 13. The assembly is closed by an externally threaded bearing housing cap 30 containing an O-ring 31, and engaging internal threads 32 of the bearing housing. Cap 30 has an internal tapered shoulder 33, which seats against the outer annulus 26 of the bearing assembly, and securely holds the bearing assembly against a shoulder 34 interiorly of the bearing housing. Shaft 13 'then extends through a seal assembly generally indicated at 35 in a tubular inlet pipe 3 6, which communicates with a fluid inlet 37, and in turn communicates with the interior of the first pump housing 15.

The seal assembly consists, as best shown in FIGURE 2, of a drive shaft seal spring 38 surrounding the shaft, and provided at its opposite ends with inside seal rings 39, the latter containing O-r-ings 40 and carbon wear rings 41. These componentsare held in position by outside seal rings 42, which in turn contain O-rings 43 and split drive shaft seal retainer rings 44, the entire assemblage being retained in the inner open end of tubular shaft 36.

Each pump housing consists of a pair of confronting conical portions 50 and 51, which are provided with confronting annular flanges 52 and 53,.having bolt holes 54 in aligned relation therethrough. When the pump is employed as a single unit, bolts are extended through the bolt holes 54, holding the parts securely in related assembly. However, in accordance with the instant invention which comprises a mul-ti-stage pump, each section 51 is connected to the adjacent opposite section 50 by a tubular flow passage 55, and, as best shown in FIGURE 1, elongated bolts 56 are extended through aligned bolt holes in the flanges 52 and 53 of adjacent housings to secure the adjacent components in tight related assembly. Nuts 57 serve to hold the bolts securely in position.

In the illustrative embodiment of the invention shown there are four pump housings 15, interconnected by tubular passageways 55, with the passageway of the last section 55a terminating in a closed end cap 60, in which the outer end of shaft 13 sea-ts for rotation. Suitable bearings or wear rings (not shown) may be contained in the end cap 60. The outlet 61. for the system-s is positioned closely adjacent the cap 60, and beyond the outermost housing 15.

As illustrated, the first and second housing sections 15 are interconnected by elongated bolts 56, as are the third and fourth, although it is to be understood that as many uni-ts may be employed as may be desired, and may be interconnected similarly.

Each pump housing contains an impeller assembly 70 having curved blades 71 and an inclined plate 72, fluid being drawn into openings formed by the inner ends .of the blades and expelled radially to the periphery, blades 74 being attached at their one end to the outer rim of the inclined plate 72 and at their other end to annular ring 73 for increasing the pressure, all in a manner identical to that of the single unit pump described in my abovementioned application.

By connecting a multiplicity of pump units of this nature in series it has been found that the effective pressure of the pump may be multiplied materially. For example, where a single pump provides a cutout pressure of less than psi. with two impellers connected in series a pressure of 137 p.s.i. is achieved while the connection of four six-inch units in series raises the cutout pressure to approximately 174 p.s.i. Friction loss in the multiple stage assembly is negligible, due to the bearing mounting and seal above described.

From the foregoing it will now be seen that there is herein provided an improved multi-stage centrifugal pump which accomplishes all of the objects of this invention, and others, including many advantages of great practical utility and commercial importance.

As many embodiments may be made of this inventive concept, and as many modifications may be made in the embodiment hereinbefore shown and described, it is to be understood that all matter herein is to be interpreted merely as illustrative and not in a limiting sense.

What is claimed is:

1. A multi-stage centrifugal pump assembly comprising a drive shaft, a plurality of pump housings concentrically mounted about said shaft, an impeller and a manifold in each pump housing fixed to said shaft, a fluid passage connecting said pump housings, a fluid inlet at one end of said passage, a fluid outlet at the other end of said passage, a bearing seal at one said one. end of said passage, a closure for said passage at said other end, one end of said shaft extending through said seal, a bearing assembly mounting on said one end of said shaft, and means for driving said shaft connected to said one end, each said impeller being in the form of a cone having blades thereon directing fluid towards the periphery of said cone and further having secondary blades positioned adjacent said periphery.

2. The structure of claim l-wherein each pump housing comprises a pair of confronting conical members having contacting annular flanges, and the flanges of one unit are connected to the flanges of an adjacent unit by common bolts.

3. The structure of claim 1 wherein said secondary blades are connected at their one ends to said periphery of said cone and at their other ends to an annular ring.

References Cited UNITED STATES PATENTS 1,080,655 12/1913 Richardson 103108 1,141,010 5/1915 Schewrmann 103-102 1,207,546 12/1916 Hards 103102 1,981,991 11/1934 Cline et al. 103-102 2,043,236 6/1936 Conant 103102 2,233,825 3/1941 Walsh et al. 103-103 2,621,601 12/1952 Stout 103108 2,670,687 3/ 1954 Waskosky et al. 10387 3,076,411 2/196 3 Guillory 103-402 FOREIGN PATENTS 217,495 1/ 1910 Germany. 251,433 5/ 1926 Great Britain.

HENRY F. RAD'UAZO, Primary Examiner. 

1. A MULTI-STAGE CENTRIFUGAL PUMP ASSEMBLY COMPRISING A DRIVE SHAFT, A PLURALITY OF PUMP HOUSINGS CONCENTRICALLY MOUNTED ABOUT SAID SHAFT, AN IMPELLER AND A MANIFOLD IN EACH PUMP HOUSING FIXED TO SAID SHAFT, A FLUID PASSAGE CONNECTING SAID PUMP HOUSINGS, A FLUID INLET AT ONE END OF SAID PASSAGE, A FLUID OUTLET AT THE OTHER END OF SAID PASSAGE, A BEARING SEAL AT ONE SAID ONE END OF SAID PASSAGE, A CLOSURE FOR SAID PASSAGE AT SAID OTHER END, ONE END OF SAID SHAFT EXTENDING THROUGH SAID SEAL, A BEARING ASSEMBLY MOUNTING ON SAID ONE END OF SAID SHAFT, AND MEANS FOR DRIVING SAID SHAFT CONNECTED TO SAID ONE END, EACH SAID IMPELLER BEING IN THE FORM OF A CONE HAVING BLADES THEREON DIRECTING FLUID TOWARDS THE PERIPHERY OF SAID CONE AND FURTHER HAVING SECONDARY BLADES POSITIONED ADJACENT SAID PERIPHERY. 